Rolando: Understood to have been watched by QPR boss Harry Redknapp this week

Redknapp is believed to be keen on the 27-year-old centre-back but a formal offer is yet to be made.

Premier League strugglers QPR are seeking defensive cover following Ryan Nelsen's announcement he will depart next week to take up his coaching post at Major League Soccer club FC Toronto.

The club are thought to be eyeing Rolando as a replacement and Redknapp's trip to Portugal has fuelled such rumours.

The Hoops, currently bottom of the Premier League and five points adrift of safety, have already struck in the transfer market this month, bringing in Loic Remy from Marseille and free agent Tal Ben Haim.

Portugal international Rolando, who has also been linked with Napoli, joined Porto from Belenenses in 2008 and has notched up over 100 appearances for the Primeira Liga club.

He has lifted the Portuguese title three times with Porto, as well as winning the UEFA Europa League, Portuguese Cup and UEFA Super Cup.